Ok, still a Harley noobie...but I'm learning.

I've read just about everything I could about this topic on here, but I'm still confused. I installed new Rush 1.75 slip ons on my 2012 Fatboy (sound great!) and I'm getting some decel popping. I used new clamps (torqued to 65lbs) and Ultra Copper and have not found any exhaust leaks. Everything else is stock.

If it's not an exhaust leak, some say it's caused by too lean AFM and some say it's too rich. Question is, if I want to get rid of it, should I go to the HD dealer and have them do some kind of a tune on it (how much?), or should I opt for a tuner (V&H fuel pak 61017 or Power Vision PV-2)? The only other mod I might make some day would be to change out the air filter. The FuelPak is cheaper, but will it work good enough and is it easy to install and use?

The popping doesn't really sound that bad, so I'd also like to know if it can cause any damage?

Appreciate your comments.
David

 

My 11 Lo popped on decel when I added pipes and race tuner. It has been dynoed, and it still pops. Dealer told me it was normal.

 

here is my 2 cents,

The decel popping is the result of being too lean at the lower throttle positions. on my stock 2012 FB it had some popping from new.

I changed the pipes to Thunderheader and ordered a Powervision2 from Fuel-moto with their dowload, the sound i wanted was there and the popping was gone. On my 2008 FXD after adding the powercomander 5 i had popping on decel. I had added fuel 5% at a time to the 0 throttle position up to 2500 rpm.

Excessive popping on decel is not normal and can be tuned out of the program with a little effort.

Craig

 

Had the same thing on an '09 with Rush slip-ons. Doebek fuel pak eliminated about 70% of it, and the rest depends on how you use the throttle. Try not to let it close too suddenly.

 

I have a 2012 Deluxe with V&H slipons and SE AC. The pipes got put on when the bike was brand new so I don't know if it had any decel pop or not with the stock mufflers. The bike had way too much decel popping for my liking so took it to the dealer for a download, nothing changed. Went with the SE tuner and dyno, 99% of the decel popping is gone and I'm a happy camper. There was no way I could stand it the way it was.

 

Check for exhaust leaks, if none, then prob not close enough to stoichiometric. My SG has an HD Pro Tuner and it pops like a 50 cal machine gun. I put a Cobra F1200 Auto tuner on my Blackline and it hardly pops at all because the A/F is real time tuned in any range or condition. Personally, I don't mind the decel after 35 years of listening to it.

 

If you plan to keep upgrading/wrenching on your scoot - might be good time to invest in tuner. You probably don't have any leaks from Rush pipes & the reduced backpressure is causing some pops. Adding tuner & adjusting fuel/air a bit will help...take a look at Dobeck - great product/support!

www.dobeckperformance.com

 

Here's my guess at the formula for decel popping.

Performance pipes + EPA + Harley Dealer Tune OR HD ECM Autotune = decel popping.

I'm guessing that your dealer won't change the map so that it is running rich enough to get rid of the popping because they have to conform to EPA specs.

Adding a different piggy back or ECM allows a non-HD dealer to make the required overrides. Your gas mileage will go down. Your bank account will go down. Your smile will turn up. I'm not sure what the state of the HD tuner for a '12 is... but if I recall you can buy SE software that is for your bike only that you can make adjustments to the stock ECM with. I don't know much about this, however, because you couldn't do that in '06 so I just chucked my stock ECM and went for a TMax. Last I heard, TMaxes were having trouble with the throttle by wire on the new HD's.

IMHO there is no debate about what causes this on an EFI system if you have no exhaust leaks. There is a slight debate about whether it causes any harm. I spent a lot of money getting rid of my decel pops. Later, I spent a lot of money fixing my cam chain tensioners (had to replace the cams, cams support, etc. and update my injectors). As it turned out, it was a good thing that I bought a TMax but at the time I was just tired of listening to the pops.

I have gone from 50 mpg to 38 mpg, any rice burner over 300 cc's can still kick my butt, and noise ordinaces will soon be the order of the day. Sometimes I'm not so sure that it is worth it... getting an old shovel and building a real hot rod would probably have been better. All of the known weaknesses of those motors have been overcome with bearings, newer ignitions, S&S carbs, and better sealants. I saw a '57 BSA Daytona go for north of $25k at auction recently. If you want to be really cool... well... it sure looked cool. A hot rod shovel can be done for about half of that.

C#

 

Thanks for some excellent info so far. Money's pretty tight right now so I want to make the little bit I have left, go a long way. I guess my real questions are:

1) I've only added the Rush slip ons. Do I need to add a better air filter too? I only wanted a better "Harley" sound and the Rush definitely make it sound better.

2) If I'm not planning any other mods, would a V&H Fuelpak be sufficient for handling decel popping? Only runs about $250

3) Is the Powervision PV-2 at $550 really the best method for eliminating decel popping? Or is there another reason is would be worth it to someone like me who doesn't ever plan to add additional mods?

Thanks again,
David

 

Throw some XIED's on there if you ain't going any further with your mods. They'll likely solve your problem and save you some greenbacks.